Roxy's Gourmet Grilled Cheese joins the ranks of Boston's newfound fleet of food trucks, capricious cousins to brick-and-mortar spots. Roxy's rules a Cleveland Circle intersection, its pigtailed-and-inked logo peering coyly from the side of the truck. Recent Emerson grad and founder James DiSabatino presides over the window with a sunny disposition, craning over the ledge, taking orders for a rotating menu of sandwiches, and passing out shots of tomato-basil soup to pass the wait. In the early spring chill, shuffling in the lot with my hands in my pockets, my soup didn't last long enough for eventual dipping, but I was perfectly placated while I watched the cooks flip rows of sandwiches. Roxy's bread of choice is a white Iggy's loaf, sliced and slathered with mayonnaise before griddling to an even brown crisp. By using mayonnaise, Roxy's trades the brine of butter for an edge-to-edge toasted crust, borders crackling where it meets toasted cheese.

For Boston restaurants who name their dishes cutely, it seems mandatory to include one riffing on the famous Fenway Park left-field wall: Roxy's is the Green Muenster ($6), which tops the aforementioned cheese with creamy daubs of guacamole and, in theory, bacon, though none was available during my visits. The entry-level Rookie ($4) is Monterey jack, a thick slice of tomato, and a smear of whole-grain mustard. On the Hillbilly Melt ($6), you'll find sliced ham and Swiss with crunchy red-pepper-and-red-onion slaw — more of a chop than a slaw. Mac & Chorizo ($6) is a slovenly sandwich of al dente elbow macaroni and mild cheddar, sweet strings of onion and chewy bites of chorizo. At first, I wanted another, but soon, I wanted a nap. Roxy's has also commissioned local pickle company Grillo's to slice rounds of their garlicky dills, which are fried in a light, crispy beer batter ($4).

Not even dessert goes ungriddled; such is the fate of the grilled cheesecake sandwich, two thick slices of tangy pound cake spread with something creamy and delicious — mascarpone? — ($4) and seared. DiSabatino explained that homemade ginger-ale floats may be on the horizon (I suppose you can't grill that). Eat on the narrow steel rim outside the truck window, or do what I did, and retreat to your car with your paper-wrapped sandwiches.

Roxy's Gourmet Grilled Cheese, located at the intersection of Chestnut Hill Avenue and Beacon Street, by Cassidy Playground in Brookline, is open various hours but frequently, on weekends, until 2 am. Check Twitter for updates @roxysgrilledchz.